Docs: Badger file permission as non-root service

plugin/storage/badger/docs/storage-file-non-root-permission.md

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+# Badger file permissions as non-root service
+
+After the release of 1.50, Jaeger's Docker image is no longer running with root privileges (in [#4783](https://github.com/jaegertracing/jaeger/pull/4783)). In some installations it may cause issues such as "permission denied" errors when writing data.
+
+A possible workaround for this ([proposed here](https://github.com/jaegertracing/jaeger/issues/4906#issuecomment-1991779425)) is to run an initialization step as `root` that pre-creates the Badger data directory and updates its owner to the user that will run the main Jaeger process.
+
+```yaml
+version: "3.9"
+
+services:
+[...]
+  jaeger:
+    image: jaegertracing/all-in-one:latest
+    command:
+      - "--badger.ephemeral=false"
+      - "--badger.directory-key=/badger/data/keys"
+      - "--badger.directory-value=/badger/data/values"
+      - "--badger.span-store-ttl=72h0m0s" # limit storage to 72hrs
+    environment:
+      - SPAN_STORAGE_TYPE=badger
+    # Mount host directory "jaeger_badger_data" as "/badger" inside the container.
+    # The actual data directory will be "/badger/data", 
+    # since we cannot change permissions on the mount.
+    volumes:
+      - jaeger_badger_data:/badger
+    ports:
+      - "16686:16686"
+      - "14250"
+      - "4317"
+    depends_on:
+      prepare-data-dir:
+        condition: service_completed_successfully
+
+  prepare-data-dir:
+    # Run this step as root so that we can change the directory owner.
+    user: root
+    image: jaegertracing/all-in-one:latest
+    command: "/bin/sh -c 'mkdir -p /badger/data && touch /badger/data/.initialized && chown -R 10001:10001 /badger/data'"
+    volumes:
+      - jaeger_badger_data:/badger
+
+volumes:
+  jaeger_badger_data:
+```